static Object unstructure(String text) {

  ret unstructure(text, false);

}

static Object unstructure(String text, final boolean allDynamic) {

  ret unstructure(text, allDynamic, null);

}

static int structure_internStringsLongerThan = 50;

// TODO: backrefs for hashmap{} etc

// classFinder: name -> class

static Object unstructure(String text, final boolean allDynamic,

  final O classFinder) {

  if (text == null) ret null;

  final L<S> tok = javaTok(text);

  final boolean debug = unstructure_debug;

  class X {

    int i = 1;

    new HashMap<Integer, O> refs;

    new HashSet<S> concepts;

    Object parse() {

      String t = tok.get(i);

      int refID = 0;

      if (t.startsWith("m") && isInteger(t.substring(1))) {

        refID = parseInt(t.substring(1));

        i += 2;

        t = tok.get(i);

      }

      // if (debug) print("parse: " + quote(t));

      if (t.startsWith("'")) {

        char c = unquoteCharacter(tok.get(i));

        i += 2;

        return c;

      }

      if (t.equals("bigint"))

        return parseBigInt();

      if (t.equals("d"))

        return parseDouble();

      if (t.equals("fl"))

        return parseFloat();

      if (t.equals("false") || t.equals("f")) {

        i += 2; return false;

      }

      if (t.equals("true") || t.equals("t")) {

        i += 2; return true;

      }

      if (t.equals("-")) {

        t = tok.get(i+2);

        i += 4;

        ret isLongConstant(t) ? (O) (-parseLong(t)) : (O) (-parseInt(t));

      }

      if (isInteger(t) || isLongConstant(t)) {

        i += 2;

        //if (debug) print("isLongConstant " + quote(t) + " => " + isLongConstant(t));

        if (isLongConstant(t)) ret parseLong(t);

        long l = parseLong(t);

        bool isInt = l == (int) l;

        if (debug)

          print("l=" + l + ", isInt: " + isInt);

        ret isInt ? (O) new Integer((int) l) : (O) new Long(l);

      }

      if (t.equals("File")) {

        File f = new File(unquote(tok.get(i+2)));

        i += 4;

        ret f;

      }

      if (t.startsWith("r") && isInteger(t.substring(1))) {

        i += 2;

        int ref = Integer.parseInt(t.substring(1));

        O o = refs.get(ref);

        if (o == null)

          print("Warning: unsatisfied back reference " + ref);

        ret o;

      }

      O o = parse_inner(refID);

      if (refID != 0)

        refs.put(refID, o);

      ret o;

    }

    // everything that can be backreferenced

    O parse_inner(int refID) {

      String t = tok.get(i);

      // if (debug) print("parse_inner: " + quote(t));

      if (t.startsWith("\"")) {

        String s = internIfLongerThan(unquote(tok.get(i)), structure_internStringsLongerThan);

        i += 2;

        return s;

      }

      if (t.equals("hashset"))

        return parseHashSet();

      if (t.equals("treeset"))

        return parseTreeSet();

      if (eqOneOf(t, "hashmap", "hm"))

        return parseHashMap();

      if (t.equals("{"))

        return parseMap();

      if (t.equals("["))

        return parseList();

      if (t.equals("bitset"))

        return parseBitSet();

      if (t.equals("array") || t.equals("intarray"))

        return parseArray();

      if (t.equals("ba")) {

        S hex = unquote(tok.get(i+2));

        i += 4;

        ret hexToBytes(hex);

      }

      if (t.equals("boolarray")) {

        int n = parseInt(tok.get(i+2));

        S hex = unquote(tok.get(i+4));

        i += 6;

        ret boolArrayFromBytes(hexToBytes(hex), n);

      }

      if (t.equals("class"))

        return parseClass();

      if (t.equals("l"))

        return parseLisp();

      if (t.equals("null")) {

        i += 2; return null;

      }

      /* in dev.

      if (!allDynamic && t.equals("run")) {

        S snippetID = unquote(t.get(i+2));

        i += 4;

        run(

      }

      */

      bool concept = eq(t, "c");

      if (concept) {

        consume("c");

        t = tok.get(i);

        assertTrue(isJavaIdentifier(t));

        concepts.add(t);

      }

      // any other class name

      if (isJavaIdentifier(t)) {

        // First, find class

        Class c;

        if (allDynamic) c = null;

        else if (classFinder != null)

          c = (Class) callF(classFinder, t);

        else

          c = findClass(t);

        // Second, check if it has an outer reference

        i += 2;

        bool hasOuter = eq(get(tok, i), "(") && eq(get(tok, i+2), "this$1");

        DynamicObject dO = null;

        O o = null;

        if (c != null)

          o = hasOuter ? nuStubInnerObject(c) : nuObject(c);

        else {

          if (concepts.contains(t) && (c = findClass("Concept")) != null)

            o = dO = (DynamicObject) nuObject(c);

          else

            dO = new DynamicObject;

          dO.className = t;

          if (debug) print("Made dynamic object " + t + " " + shortClassName(dO));

        }

        // Now, save in references list.

        if (refID != 0)

          refs.put(refID, o != null ? o : dO);

        // NOW parse the fields!

        new Map<S, O> fields;

        if (i < tok.size() && tok.get(i).equals("(")) {

          consume("(");

          while (!tok.get(i).equals(")")) {

            String key = unquote(tok.get(i));

            i += 2;

            consume("=");

            Object value = parse();

            fields.put(key, value);

            if (tok.get(i).equals(",")) i += 2;

          }

          consume(")");

        }

        if (o != null)

          if (dO != null) {

            if (debug)

              printStructure("setOptAllDyn", fields);

            setOptAllDyn(dO, fields);

          } else

            setOptAll(o, fields);

        else

          dO.fieldValues.putAll(fields);

        if (o != null)

          pcallOpt(o, "_doneLoading");

        return o != null ? o : dO;

      }

      throw new RuntimeException("Unknown token " + (i+1) + ": " + t);

    }

    Object parseSet(Set set) {

      set.addAll((L) parseList());

      return set;

    }

    Object parseLisp() {

      consume("l");

      consume("(");

      List list = new ArrayList;

      while (!tok.get(i).equals(")")) {

        list.add(parse());

        if (tok.get(i).equals(",")) i += 2;

      }

      consume(")");

      return newObject("main$Lisp", (S) list.get(0), subList(list, 1));

    }

    Object parseBitSet() {

      consume("bitset");

      consume("{");

      new BitSet bs;

      while (!tok.get(i).equals("}")) {

        bs.set((Integer) parse());

        if (tok.get(i).equals(",")) i += 2;

      }

      consume("}");

      return bs;

    }

    Object parseList() {

      consume("[");

      List list = new ArrayList;

      while (!tok.get(i).equals("]")) {

        O o = parse();

        //if (debug) print("List element type: " + getClassName(o));

        list.add(o);

        if (tok.get(i).equals(",")) i += 2;

      }

      consume("]");

      return list;

    }

    Object parseArray() {

      S type = tok.get(i);

      i += 2;

      consume("{");

      List list = new ArrayList;

      while (!tok.get(i).equals("}")) {

        list.add(parse());

        if (tok.get(i).equals(",")) i += 2;

      }

      consume("}");

      if (type.equals("intarray"))

        return toIntArray(list);

      return list.toArray();

    }

    Object parseClass() {

      consume("class");

      consume("(");

      S name = tok.get(i);

      i += 2;

      consume(")");

      Class c = allDynamic ? null : findClass(name);

      if (c != null) ret c;

      new DynamicObject dO;

      dO.className = "java.lang.Class";

      dO.fieldValues.put("name", name);

      ret dO;

    }

    Object parseBigInt() {

      consume("bigint");

      consume("(");

      S val = tok.get(i);

      i += 2;

      if (eq(val, "-")) {

        val = "-" + tok.get(i);

        i += 2;

      }

      consume(")");

      ret new BigInteger(val);

    }

    Object parseDouble() {

      consume("d");

      consume("(");

      S val = unquote(tok.get(i));

      i += 2;

      consume(")");

      ret Double.parseDouble(val);

    }

    Object parseFloat() {

      consume("fl");

      S val;

      if (eq(tok.get(i), "(")) {

        consume("(");

        val = unquote(tok.get(i));

        i += 2;

        consume(")");

      } else {

        val = unquote(tok.get(i));

        i += 2;

      }

      ret Float.parseFloat(val);

    }

    Object parseHashMap() {

      i += 2;

      return parseMap(new HashMap);

    }

    Object parseHashSet() {

      consume("hashset");

      return parseSet(new HashSet);

    }

    Object parseTreeSet() {

      consume("treeset");

      return parseSet(new TreeSet);

    }

    Object parseMap() {

      return parseMap(new TreeMap);

    }

    Object parseMap(Map map) {

      consume("{");

      while (!tok.get(i).equals("}")) {

        O key = parse();

        consume("=");

        Object value = parse();

        map.put(key, value);

        if (tok.get(i).equals(",")) i += 2;

      }

      consume("}");

      return map;

    }

    void consume(String s) {

      if (!tok.get(i).equals(s)) {

        S prevToken = i-2 >= 0 ? tok.get(i-2) : "";

        S nextTokens = join(tok.subList(i, Math.min(i+4, tok.size())));

        fail(quote(s) + " expected: " + prevToken + " " + nextTokens + " (" + i + "/" + tok.size() + ")");

      }

      i += 2;

    }

  }

  return new X().parse();

}

static boolean unstructure_debug;